3.3 Explain disaster recovery (DR) concepts.

Question 1

What is a RPO with regards to Disaster Recovery?

Answer 1

• Recovery Point Objective
• This is the time from that last data recovery point to the outage.
• How much data loss is acceptable?
• We would like this to be near-zero.

Question 2

What is a RTO with regards to Disaster Recovery?

Answer 2

• Recovery Time Objective
• The ability to get back to a particular service level in a certain timeframe.

Question 3

What is MTTR with regards to Disaster Recovery?

Answer 3

• Mean Time to Repair
• The average time required to fix the issue.

Question 4

What is MTBF with regards to Disaster Recovery?

Answer 4

• Mean Time Between Failures
• This is the average time between failures.

Question 5

What is a cold site?

Answer 5

• No hardware is located at this site.
• Empty building.
• No data; bring it with you.
• No people; bus them in.

Question 6

What is a warm site?

Answer 6

• Big room with rack space; you would just need to bring the hardware.
• Hardware could be staged, you would just need to bring the software and data.

Question 7

What is a hot site?

Answer 7

• An exact replica of your data center or as close as you can make it.
• Constantly updated (applications and software)
• Automated replication.
• Flip a switch and everything moves.

Question 8

With regards to high-availability approaches, what does it mean to be “active-active”?

Answer 8

• two devices are installed and configured and used simultaneously.
• These set-ups are more complex to design and operate as data can flow in many different directions.

Question 9

With regards to high-availability approaches, what does it mean to be “active-passive”?

Answer 9

• Two devices are installed and configured but only one operates at a time.
• If the primary fails, then the secondary takes over as the primary device.

Question 10

What is a tabletop exercise?

Answer 10

• Sit around a conference table and go through what you “would” do if you were implementing a disaster recovery situation, step by step process review.

Question 11

What is a validation test?

Answer 11

• Testing yourself using well-defined rules of engagement (do not touch production systems).
• Very specific scenario and limit time to run the event.